Phd Guiding issue

Hi All,This is a bit difficult to describe so i'll give it my best shot. During a typical dslr imaging session I run:1. Cartes du Ciel2. EQASCOM3. Backyard EOS4. PHD GuidingAfter everything is running and while on an imaging run I notice that PHD Guiding just "disappears"...on my Win 7 Pro task bar the PHD Guiding icon is depressed but I can't actually see the app window. When I press the icon I get windows beeps but that's it. Ive even minimized all of the other programs and all I see is my wimdows desktop. Any ideas??? Im at a lost. I also notice that initially guiding is spot on then lapses then goes back to spot on...

I think the key is to not minimize any thing. I've had a few problems in the past running my Vista laptop. I just leave everything up and generally have no problems. I don't run as much as you do but I have noticed if I minimized PHD then it ran into issues. I usually run Cartes du Ciel (2.76c), PHD and CCDOPS or Nebulosity2. I never totally minimize anything. William